Metal closure

ABSTRACT

The disclosure relates to an improvement in construction of convenience opening type bottle closures. The closure comprises an inner liner cap or gasket engaging the bottle finish and an outer metal closure crimped around the bottle finish or rim. In the top of the outer cap there is a spaced pair of embossed projections which are located to place the pull ring member in tension, that is, to load it in a taut condition and prevent tear strip fracture, accidentally, while the package is in transit or handling prior to opening by the user.

United States Patent 1191 Amos [4 Sept. 10, 1974 METAL CLOSURE Primary Examiner-George T. Hall :r g sv n l; s i l bg Attorney, Agent, or FirmJ. R. Nelson; E. J. Holler ss1gnee: Vens- 01s, 11c., o e 0, 1o

[22] Filed: July 17,1972 [57] ABSTRACT [21] App], N 272,679 The disclosure relates to an improvement in construction of convenience opening type bottle closures. The closure comprises an inner liner cap or gasket engag- [2%] :LS. (g1. "K215142525 ing the bottle finish and an outer metal closure lit. B 5 d 4 l0 crimped around the bottle finish or rim In the p of [58] Fleld of Search 215/46 A, 220/54 the outer p there is a Spaced p of embossed p jections which are located to place the pull ring mem- [56] References and her in tension, that is, to load it in a taut condition and UNITED STATES PATE prevent tear strip fracture, accidentally, while the 2,743,129 7/1973 Willis et al 215/46 A package is in transit or handling prior to opening by 3,403,81] 10/1968 Moller et al.. .l 220/54 the U561. 3,556,336 1/1971 Coop 215/46 A 3,643,832 2/1972 Khoury 220/54 2 Claims, 4 Drawing Figures 1 METAL CLOSURE BACKGROUND OF THE INVENTION The present invention relates to convenience opening closures for bottles or like containers, such as the closure disclosed in US. Pat. No. 3,561,63l. The closure of this type is placed over and about the bead at the mouth rim of the bottle and compressed or crimped thereon by a capper. In the top panel of the closure there is a pull ring or tab that is riveted onto an end portion of an integral, scored tear strip formed in the metal of the cap. This pull ring, when it is lifted, severs the metal at the one end of the tear strip from the top of the cap and subsequently, by pulling the ring, the tear strip eventually severs the skirt edge or wire bead of the cap thereby loosening it and freeing it for removal from about the finish or bead of the bottle. In fastening the pull ring to the tear strip, score line fatigue and fracture may be experienced during transportation and handling of the closure or the closure-bottle combination.

SUMMARY OF THE INVENTION It is, therefore, one of the important objects of the present invention to obviate the problem of fatigue and/or fractures of themetal of the tear strip by providing means that will prevent vibrations traveling through the pull ring into the rivet area whereat the pull ring is attached to the tear strip of the closure. It is apparent from failures of this type experienced that such vibrations transmitted through the pull ring member and applied at the scored tear strip region will cause fractures to form in the score line of the tear strip.

Another important feature of the invention is the novel structure by which the vibration problem is overcome in the present invention; namely, by the provision of a pair of spaced, embossed projections in the metal cap outside the scored, tear strip area that project into surface contact with the underside of the pull ring member and in the vicinity of the rivet so as to hold the pull ring in some tension and snug. This will reduce the vibrations and dampen the transmission of vibration into the rivet connection with the tear strip, overcoming the fatigue and fracture problem.

The invention is especially adapted to pressure containers, such as beer or carbonated beverage products under a range of pressure of 2.5 to 7 volumes. Fracture of the closure prematurely, and venting of the headspace in the container through the fracture invariably means spoilage of the product packaged in the container. A similar result may occur if a vacuum packaged product is prematurely vented, i.e., the closure factures allowing headspace vacuum to be lost. The invention, therefore, has apractical value in either type of package.

Secondarily, the disclosed embossed portions of the top panel of the metal closure also lends strength and rigidity to the top panel of a the closure.

Various other objects of the invention will occur to those skilled in the art from the following disclosure and detailed description of the appended drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a metal cap blank wherein the scored tear strip has been formed as well as the embossed projections of the invention;

FIG. 2 is a sectional elevational view showing the tool and step of forming the embossed projections in the cap blank wherein the forming tool engages the underside of the cap blank;

FIG. 3 is a plan view of the completed closure of the invention; and

FIG. 4 is an elevational view, partly sectioned along line 4--4 of FIG. 3, showing the closure applied onto a bottle.

DESCRIPTION OF THE INVENTION Referring to the drawings, FIG. 1 illustrates a closure blank 10 which comprises a stamped circular flat section of sheet metal. The preferred embodiment has the blank 10 of aluminum material on which is formed a substantially continuous score line, indicated at 11.

Score line 11 is formed in blanking dies which define the configuration of the tear strip I2 bounded by the line 11. In forming score line 11, blanking dies of conventional type (not shown) reduce the thickness of the metal thereat to form a weakened segment of the metal. When this segment of the metal is subjected to shearing force, the metal will sever along the score line 11; however, prior to the application of such shearing force, the metal of the blank 10, when in cap form as described hereinafter, will hold the product and pressure internally of the bottle and retain the cap as an integral metal closure on the container.

The score line 11, in a preferred form, is outlined to form the tear strip 12' located well beyond the axial center of the cap and extending across and toward the other edge of the cap 13.

The curved nose section 11a of tear strip 12 is formed to center on and abut the inner edge of the straight side segments 11b and 11c of the scoreline. The nose section lla accomodates' the location of a ring pull device 14 and a rivet 15 formed from metal within the nose section 11a (see FIG. 3). The ring pull or pull tab device 14 comprises the ring or tab portion and a yoke portion 23 by which the device 14 is fastened to the tear stripand cap top panel. The leg segments 1 lb and 1 1c of the score line have differing rela tionships with the free outer edge 16 of the blank 10 which will form a rolled edge or wire at the lower edge perimeter of the skirt 17 of the metal cap formed from blank 10.

Blank 10 is formed in a progressive die-set. In addigenerally on FIG. 2, the tool 19 being incorporated in I any known convenient manner in the die set (not shown). Tool 19 used on an aluminum blank 10 may have a conical taper of an included angle at the apex of about 50 (FIG. 2) and approximately 0.050 inch radius at the nose of the tool. While in the flat blank 10,

the metal of the projections 18 are raised or embossed to a height of about 0.020 to 0.040 inch. The preferred height of the projections is 0024-0026.

As shown on FIGS. 3 and 4, blank 10 is processed through dies to form the metal cap, indicated generally as 13. Cap 13 includes the top central panel 25 and raised therefrom in a radial direction is annular portion 20 providing a packing groove to be disposed over the bottle finish rim. The periphery of portion 20 has a corner radius 21 connecting with circumferential skirt 17, its lower end or free edge being rolled upon itself as peripheral wire 22 of the cap 13.

Ring pull device 14 is secured to the tear strip 12 adjacent the curved nose portion 11a of the score line by means of the integral fivet 15a inserted through an aperture in the tongue 23 of the device and the rivet is flattened as 15 (FIG. 3). Ring pull device 14 is fastened to the nose section of the tear strip to function as a lever. The tongue 23 extends from rivet 15 to join with the ring of device 14 at about the inner reaches of score line 11a, and the ring device extends outside the score line 11 to bear against the top panel portion 25 of the cap. if the ring pull 14 is lifted by inserting the finger under its free end remote from the rivet, the opposite forward end of the ring pull engages panel 25 outside score line 11a and functions as the fulcrum point for the lever action. The connection of tongue 23, integral with pull ring 14, and rivet l5 lifts tear strip 12 causing it to fracture in the underlying area of score line 11a. Continued pulling of the ring pull 14 tears the strip 12 along score 11b and 11c to open the cap of the bottle B. The bottle B is constructed of glass and includes a mouth opening defined by a circular rim on which radially outwardly there is forrned an annular bead. This rim and bead about the mouth of bottle B forms the bottle finish over which the closure 13 is applied and fastened by capping (crimping) skirt portion 17.

Longitudinally, approximately, of scored tear strip 12 is an embossed strengthening rib 26. This aids in the removal of the tear strip until the wire 22 of the skirt is fractured to release the encircling crimp of the cap 13 on the underlying bead of the bottle B. In the form shown on FIG. 4, the closure includes a snap-on, plastic, full liner cap 24 which covers the mouth of bottle B and overlies the seal surfaces of the bottle finish. Another form suitable to be combined with cap 13 is a flowed-in gasket of plastisol, organisol or rubber compound which annularly seals the mouth of bottle B about the rim or finish surfaces.

In staking or riveting the ring pull member 14 onto tear strip rivet 15, the underside of the ring pull is pulled taut into engagement with the embossed projections 18a and 18b. This connection maintains the assembly in tension and taut engagement between the dimple-like projections 18 and the ring pull member is maintained. Since this engagement is very near or in close proximity to the arcuate score 11a and the rivet l5, vibration is dampened and this end of the ring pull member 14 will be prevented from rocking and vibratory movement sufficiently to overcome accidental fractures of the tear strip from the rest of the closure in the top panel portion.

Although it is not shown on the drawings. the liner cap 24 provides for proper pressure venting to enable proper function and safety of the cap upon opening it.

Having shown and described a preferred embodiment of the invention, changes, modifications and substitutions, other than as may be mentioned herein, may be made by those ordinarily skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims; wherein 1 claim:

1. A metal cap for a glass bottle comprising a top panel portion, an integral tear strip in said cap defined by a reversing score line, said tear strip including a nose portion at the reversing segment in said top panel, a ring pull member of substantially endless configuration defining a finger receiving opening near its one end and having an integrally connected yoke, a rivet receiving aperture adjacent the free end of said yoke for connecting the ring pull member near its other forward end to said top panel, rivet means through said aperture, connecting the ring pull member securely to said nose end of the tear strip, the ring pull member partly overlying said tear strip and partly overlying said top panel out side the tear strip operable for lever action in severing the nose end of the tear strip in said top panel, the top panel providing a fulcrum point for the other forward end of the ring pull member by engaging the top panel forward of the rivet means and outside of said tear strip, plural dimple-like raised projections on the outer top surface of said top portion disposed on either side of said nose end of the tear strip and forward of the rivet means, each raised projection being located outside the tear strip, rearward of said fulcrum point and intermediate said fulcrum point and the rivet means, said plural projections tightly engaging the ring pull member near its other forward end and forward of said rivet and rearward of said fulcrum point, said plural engagements of the ring pull member on the top panel holding a cantilevered portion of the forward end of said ring pull member spaced from the top panel at said fulcrum point and maintaining said ring pull member in tension about said rivet in an assembled riveted position; thereby dampening vibration of the ring pull member in its assembled position on the closure.

2. The closure of claim 1, wherein said plural pimplelike, raised projections each extend above the level of the adjacent top panel surface a distance within the range of 0.020-0.040 inch. 

1. A metal cap for a glass bottle comprising a top panel portion, an integral tear strip in said cap defined by a reversing score line, said tear strip including a nose portion at the reversing segment in said top panel, a ring pull member of substantially endless configuration defining a finger receiving opening near its one end and having an integrally connected yoke, a rivet receiving aperture adjacent the free end of said yoke for connecting the ring pull member near its other forward end to said top panel, rivet means through said aperture, connecting the ring pull member securely to said nose end of the tear strip, the ring pull member partly overlying said tear strip and partly overlying said top panel outside the tear strip operable for lever action in severing the nose end of the tear strip in said top panel, the top panel providing a fulcrum point for the other forward end of the ring pull member by engaging the top panel forward of the rivet means and outside of said tear strip, plural dimple-like raised projections on the outer top surface of said top portion disposed on either side of said nose end of the tear strip and forward of the rivet means, each raised projection being located outside the tear strip, rearward of said fulcrum point and intermediate said fulcrum point and the rivet means, said plural projections tightly engaging the ring pull member near its other forward end and forward of said rivet and rearward of said fulcrum point, said plural engagements of the ring pull member on the top panel holding a cantilevered portion of the forward end of said ring pull member spaced from the top panel at said fulcrum point and maintaining said ring pull member in tension about said rivet in an assembled riveted position; thereby dampening vibration of the ring pull member in its assembled position on the closure.
 2. The closure of claim 1, wherein said plural pimple-like, raised projections each extend above the level of the adjacent top panel surface a distance within the range of 0.020-0.040 inch. 